What's concerning though entering February is there just doesn't seem to be much in the way of cold air into Canada...PAC air continues to be flooded into Canada.
I would think something has to give entering the second week of January with forecast models indicating such an intense ULJ...looks like you get a situation where the STJ and PJ phase and there's a pretty significant storm with that and then a major pattern change behind it? Didn't we actually experience something similar last winter (and around the same time?)...there was the record ulvl winds measured across several Northeast balloon launch locations
GFS does look like a potentially good setup for severe in the south around 180-hours! No strong EML signals but some EML air may make the ride from Mexico
That's an excellent point.
Combine a fast flow with numerous pieces and it's nothing but chaotic hell with solutions which range from OTS to roof crushing snows.
But to your initial point...I get what you're saying...and actually given the fast flow and room for phasing not to happen...well an intense system is not as certain.
What is pretty certain by this point (with further strengthening from ensemble support) is this is going to be a pretty intense system. But agreed...the NAM (even though we're taking 84-hours) is a rather potent look. Much more compact and intense with the vorticity whereas the GFS is more hung back and not nearly as defined with the trough. I was also look at that jet streak over the ridge arc...that is certainly going to be a factor.
It does seem like there is fairly good agreement about how the pattern evolves across the PAC and building of the ridge into the west. Significant differences then occur with how everything evolves downstream. One thing that's been in the back of my mind is how this system evolves in the southeast. Right now models aren't too enthused with the development of convection across the southeast or off the coast but if that were to change that could add to this shortwave mess.
12z NAM gets into the range of Friday evening now...the differences in H5 between the models even for Friday evening (which isn't entirely that far out there) is insane. Hopefully over these next 24-hours there is some sort of clustering/agreement of the large-scale features.
WTH has been wrong with this page?
It's been horrific the past several months
https://www.nws.noaa.gov/mdl/synop/products/bullform.all.php#bottom
Thank God for this
https://leonardo.met.tamu.edu/Weather_Interface/index.php
QPF shouldn't be a problem with this system (which hopefully will work out to our benefit) but take a look at the individual members for 12z and 18z Saturday...just all over the place. Really tough to generate any sort of idea right now on what to expect.
Very true.
All the reason why I think in this situation you have to be careful with using just an EPS mean.